(1) Field of the Invention
The present invention relates to a gauge used in, for example, vehicles or ships, and more particularly, a gauge having a pointer configured to travel across a gauge face based upon input received from measurement.
(2) Description of the Related Art
A moving body such as vehicle or ship is equipped with a gauge configured to display multiple types of information on a display field, and to be viewed by a user thereof. The gauge includes a combination meter comprising a speedometer for indicating a vehicle speed, a tachometer for indicating an engine speed, a fuel gauge for presenting fuel level information to user, a temperature gauge for indicating the temperature of cooling water, and so on.
FIGS. 7 and 8 show one example of the foregoing conventional combination meter. This type of conventional combination meter is, for example, disclosed in Japanese Publication of Non-Examined Patent Application 2005-98751.
Referring to FIGS. 7 and 8, the vehicle combination meter 100 is shown to include a speedometer A, a tachometer B, and a case 102 for accommodating the speedometer A and the tachometer B.
The speedometer A is shown to include a dial face 104A having a display field consisting of scales 141A and numbers 142A arranged in an arcuate pattern, a pointer 103A configured to travel across the display field and to indicate a position on the display field, a loop belt 111a connected to the pointer 103A, a drive pulley 115A and a driven pulley 118 configured to move the loop belt 111A along its longitudinal direction (indicated by an arrow “E” in FIG. 8) in order to drive the pointer 103A, a motor 113A configured to rotate the drive pulley 115A based on input received from measurement, and a tension member 119A configured to provide the belt 111A with enough tension to prevent sag of the belt 111A.
The device 119A is shown to include a pulley 116A disposed in the outside of the periphery of the loop belt 111A, and a coil spring 117A pulling the pulley 116A toward the inside of the periphery of the loop belt 111A.
The tachometer B is shown to include indicia 141B arranged in an arcuate pattern, a dial face 104B including a display field having numbers 142A and disposed inside the dial face 104A, a pointer 103B configured to travel across the display field and to indicate a position on the display field, a loop belt 114B connected to the pointer 103B, a drive pulley 115B configured to move the loop belt 111A along its longitudinal direction (indicated by an arrow “E” in FIG. 8) in order to drive the pointer 103B, a motor 113B configured to rotate the drive pulley 115B based on input received from measurement, and a tension member 119B configured to provide the belt 111B with enough tension to prevent sag of the belt 111B.
The device 119B is shown to include a pulley 116B disposed outside of the periphery of the loop belt 111B, and a coil spring 117B pulling the pulley 116B toward the inside of the periphery of the loop belt 111B.
Because in the foregoing speedometer A the pointer 103A is driven by means of the belt 111A, there is a space in the center of the speedometer A. The tachometer B can be formed within the foregoing space. Moreover, each of the speedometer A and the tachometer B includes the tension members 119A and 119B respectively, thus preventing the sag of the belts 119A and 119B.
Meanwhile, in the foregoing combination meter 100 mainly used in vehicles, the tension members 119A and 119B are respectively configured to draft or pull the pulleys 116A and 116B by means of the coil springs 117A and 117B. With the foregoing construction, frictional resistance between a shaft for supporting the pulleys 116A and 116B and a shaft bearing is inclined to increase, and therefore the higher torque-motors 113A and 113B are required. Furthermore, the belts 111A and 111B cannot move smoothly, and thus allowing the imprecise pointing of the pointers 103A and 103B.